Eastern Pacific Basin Tropical Cyclones

Hurricane Orlene Forecast Discussion


000
WTPZ41 KNHC 011450
TCDEP1

Hurricane Orlene Discussion Number  11
NWS National Hurricane Center Miami FL       EP162022
900 AM MDT Sat Oct 01 2022

Conventional satellite imagery and a recent SSM/IS overpass indicate 
that Orlene is becoming better organized, with the central 
convection becoming more symmetric and starting to develop into an 
eyewall.  There have also been hints of an eye on infrared imagery. 
Satellite intensity estimates at 12Z were in the 55-65 kt range, and 
since that time estimates from the CIMSS Advanced Dvorak Technique 
have increased to over 70 kt.  Based on this data, Orlene is 
upgraded to a hurricane with an initial intensity of 65 kt.  An Air 
Force Reserve Hurricane Hunter aircraft is scheduled to investigate 
Orlene later today.

Orlene should be in a moist and light-shear environment for about
the next 24 h, and with the increased core organization steady to
rapid intensification is expected.  The new intensity forecast
calls for a peak intensity of 80 kt in about 24 h.  After that,
strong southwesterly shear should cause steady to rapid weakening
until landfall in Mexico.  This should be followed by dissipation
over the mountains of northwestern Mexico between 72-96 h.  While
it cannot be ruled out that Orlene could reach mainland Mexico as a
hurricane, the chances of that have decreased since yesterday based
on the current trends and guidance.  The new intensity forecast has
some adjustments from the previous forecast and lies near or at the
upper edge of the intensity guidance.

Orlene continues moving slowly northward at 360/4 kt, to the west of 
a mid-level ridge. After about 12 h, the cyclone should turn 
north-northeastward in the flow between this ridge and an 
upper-level trough seen in water vapor imagery over northwestern 
Mexico and the northern Baja California peninsula. This 
north-northeastward motion is forecast to continue until Orlene 
dissipates over mainland Mexico.  The track guidance is fairly 
tightly clustered around this track, although the GFS is a bit to 
the right of the other models. The new forecast track is close to 
the various consensus models and is just a little to the left of the 
previous forecast.

Based on the the forecast track, intensity, and wind radii, a
Hurricane Warning has been issued for Las Islas Marias.


Key Messages:

1. Hurricane conditions are expected in the Islas Marias Sunday 
night, with tropical storm conditions beginning late Sunday. 
Hurricane conditions are possible over portions of the west-central 
mainland Mexico starting on Monday.  Tropical storm conditions are 
expected within the tropical storm warning area along the 
west-central coast of Mexico on Sunday. Tropical storm conditions 
are possible over other portions of southwestern and west-central 
Mexico in the tropical storm watch area tonight or Sunday.

2. Heavy rainfall from Orlene is expected to lead to flash flooding,
as well as possible landslides in areas of rugged terrain in
Southwest Mexico through Monday evening.


FORECAST POSITIONS AND MAX WINDS

INIT  01/1500Z 17.6N 107.0W   65 KT  75 MPH
 12H  02/0000Z 18.3N 107.0W   70 KT  80 MPH
 24H  02/1200Z 19.2N 106.8W   80 KT  90 MPH
 36H  03/0000Z 20.5N 106.6W   75 KT  85 MPH
 48H  03/1200Z 21.6N 106.3W   65 KT  75 MPH
 60H  04/0000Z 22.8N 105.8W   55 KT  65 MPH...INLAND
 72H  04/1200Z 24.0N 105.4W   25 KT  30 MPH...INLAND
 96H  05/1200Z...DISSIPATED

$$
Forecaster Beven



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